International Journal of Materials Engineering Innovation (18 papers in press)
Friction and Wear Behavior of HVOF Sprayed Cr2O3-TiO2 Coatings on Aluminum Alloy
by Pradeep Kumar G S, Keshavamurthy R, Prabhu Akhil M, Kiran K, Mervin Thomas, Vijay Tambrallimath, Gurumoorthy S. Hebbar
Abstract: This study investigates the tribological behavior of Cr2O3-TiO2 composite coatings deposited on Aluminum 6061 alloy. Cr2O3-TiO2 composite coatings were deposited by High velocity oxyfuel (HVOF) technique. Developed coatings were subjected to microstructure studies, microhardness test (ASTM E92), friction and wear test (ASTM G99). Pin-on-disc machine was used to evaluate friction and wear characteristics of Cr2O3-TiO2 coatings. Effect of sliding velocity (0.314-1.26m/s) and load (20N-100N) on friction and wear characteristics of Cr2O3-TiO2 coatings were studied and compared with uncoated aluminum alloy. Results showed 54% improvement in hardness of Cr2O3-TiO2 coatings in comparison with aluminum alloy. Coefficient of friction and wear rate decreases by 12% and 48% respectively when evaluated with uncoated aluminum alloy. Coefficient of Friction (COF) and wear rate increases with increase in load and sliding velocity for both coatings and substrate. However, Cr2O3-TiO2 coatings showed lower wear rate and COF at all the loads and sliding velocities studied when compared with uncoated aluminum alloy. Worn out surfaces of uncoated and Cr2O3-TiO2 coated surfaces were subjected to SEM analysis to understand the wear mechanisms in composite coatings.
Keywords: HVOF Coatings; Cr2O3; TiO2; Al6061 alloy; friction and wear; Hardness.
Effect of Cu co-doping on the microstructure and optical properties of alumino-zinc thin films for optoelectronic applications
by Ali Abou Hammad1, Amany El Nahrawy, Doaa Atia, Hanaa El-madany, Abdelfatah Mansour
Abstract: The effect of copper (Cu) co-doping on the microstructure and optical properties of zinc aluminate (AZO) thin films have been investigated. The micro-structure of prepared (Cu/AZO) thin films were described by X-ray diffraction (XRD), Fourier Transform-Infrared (FTIR), and scanning electron microscopy (HR/SEM). The optical properties are studied via UV-Vis spectrophotometry system. The XRD shows a cubic crystalline phase of the pure film and the addition of Cu did not change the cubic structure in the doped films. The vibrational bands due to the CuO bond have been observed at 415- 851 cm-1 in the FTIR spectra of Cu/AZO films. HR-SEM shows that both pure and doped films are quite homogeneous with good connectivity and the grain boundaries increase with increasing Cu which leads to enhancement of densification and the crystallinity of the films. Optical investigations of Cu/AZO films show a decrease in the bandgap values from 3.87 eV to 3.83 eV with increasing of Cu contents.
Keywords: Co-doping; Microstructure; Optical properties; Alumino-zinc; AlZnO-Thin films; Optoelectronic.
Sol-gel preparation of bioactive nanoporous (Al2O3: CuO: SiO2): dielectric properties and wastewater decontamination
by Amany El Nahrawy, Bahaa Hemdan, Ahmed Ali, Ahmed Youssef, Ali Abou Hammad
Abstract: The morphological and dielectric properties of bioactive sol-gel alumino-copper silicate nanoporous are characterized. It characterized by sharp diffraction peaks confirming the high crystallinity. Alumino-copper silicate was utilized as a disinfecting agent for wastewater disinfection. The growth inhibitory effect of alumino-copper silicate sanitizer was investigated against various categories of microbial pathogens. Toxicity assay of fabricated alumino-copper silicate nanoporous was measured. The acquired results disclosed that target pathogenic microbes in the raw wastewater sample have been inactivated when subjected to 100 mg/L of fabricated alumino-copper silicate. Likewise, results could not discover any deleterious and poisonous influences for the Vibrio fischeri bacterium and HEp-2 cell line of such nanostructures subsequently, it will be safe for use in water treatment. This investigation, therefore, recommends that the prepared alumino-copper silicate could be considered a future substitute marvelous and sustained-active disinfectant for the production of pathogenic free treated wastewater for recycling in many different applications.
Keywords: Bioactive silicate-nanoporous; aluminosilicate; pathogenic microbes; MIC; toxicity; decontamination; wastewater management.
DEVELOPMENT AND WEAR RESISTANCE EVALUATION OF EPOXY RESIN COMPOSITE REINFORCED WITH COW HORN AND CORN COB
by Olamide Ariwoola, John Taiwo, Taiwo Abioye, Isiaka Oladele
Abstract: In this work, epoxy resin composites reinforced with varying compositions (0-20 wt.%) of cow horn (CH) and corn cob (CC) particles were developed. The microstructure, hardness and wear resistance of the composites were investigated. The microstructure analysis revealed that the CC appeared to be fibre-like while the CH appeared as particles in the epoxy resin matrix. The particles content and distribution were enhanced as the CH composition in the composites increased. Compared to the unreinforced sample, the composite started showing improvement in hardness at 6 wt.% CH content (10.1 HV). This increased with increase in CH content and maximum was found at 20 wt.% CH (18.6 HV). CC additions have no considerable influence on the composite hardness. The entire composites exhibited lower wear rate compared with the epoxy resin sample. The least wear rate was found at 20 wt.% CH. CH reinforcement enhanced the composite wear properties than the CC.
Keywords: Polymer composites; Epoxy resin; Agro-waste products; Reinforcements; Wear resistance; Hardness; Microstructure; Cow horn; Corn cob; Stir casting.
Corrosive Nature of the Wetting Behavior Modified AISI 304 Stainless Steel with a Surface Microgroove
by K. Sureshvarr, Kannan R, Abhilash Kumar Nair , Sairam Krishna R, Yaswanth Varikuti , Abhishek Gollapalli , Sivashanmugam P
Abstract: Corrosive nature of the stainless steel surfaces causes material losses which, in turn, affects the structural stability of structure. The corrosion of AISI304 surfaces can be controlled by decreasing the contact between the aqueous corrosive media and the material surface. The modifications in corrosion of AISI304 surfaces were investigated experimentally by enabling small surface area of 5 mm by 5 mm cross section of material surface using single microgroove of different sizes and shapes such as U, V, and inverted cut cone. In addition to superhydrophobic behavior of modified area, the liquid drop established anisotropic wetting behavior, i.e., the static contact angle of the liquid drop is higher in the direction perpendicular to groove than the one measured in the direction of groove. The static contact angle was found to decrease with increase in geometrical parameter of the groove, i.e., the ratio between the groove width to groove depth. This behavior, in turn, increased the contact area of the liquid drop. The corrosion measurements such as corrosion current, polarization resistance, and corrosion rate have been carried out using potentiodynamic polarization clearly indicate a relationship with wetting behavior by the liquid drop and geometrical parameter of the single microgroove.
Keywords: corrosion resistance; wetting; physical microstructure; superhydrophobicity; linear polarization.
Fabrication and Tribological Studies of Al-CSA Composite Using RSM
by Siva Sankara Raju R, Venkata Siva B
Abstract: Aluminium based metal matrix composite (AMC) is prepared from coconut shell ash particles (CSA) and investigated the tribological performance of the prepared composites. Al-CSA composite is fabricated via stir casting route and tested tribological performance with Pin-on -Disc tester. Response surface methodology (RSM) based on 24 face central composite factorial design (CCF) has been employed for design of experiments. The effect of operating variables such as normal pressure (A - Kg/cm2), % of CSA (B - Vol. %)), sliding distance (C -m) and sliding velocity (D m/s) on the wear rate (Wr - mm3/m) and coefficient of friction (CF) have been analyzed. Analysis of variance (ANOVA) test reveals that normal pressure is the major influencing variable on wear rate and coefficient of friction. Interaction plots revealed that, wear rate of composite increased with an increase in pressure and sliding distance due to severe plastic deformation, delamination and decohesion of particles. Also, wear rate increased with sliding velocity up to 1.4m/s and then decreased due to the effect of work hardening, likewise, wear rate increased by increasing volume of CSA, owing to hardness of the composite. Regression analysis revealed that, normal pressure has the positive effect on coefficient of friction and the other three variables have a negative effect. Confirmatory tests are conducted and observed that, the error of the regression model is within the range of acceptance, i.e. 5%.
Keywords: Coconut shell Ash; Wear rate; Coefficient of friction; ANOVA; CCF; RSM.
Utilization of Fly Ash (FA) by Synthesizing FA-ZnO Composite as Semiconducting Material
by S.S. Panda, H.P. Tripathy, P. Pattanaik, D.K. Mishra, S.K. Kamilla
Abstract: In consideration to synthesize low value added fly ash (FA) to high value added product, an attempt has been carried out to synthesizecomposite materials having semiconducting properties out of the mixture of industrial waste fly ash (FA)and zinc oxide (ZnO). A series of FA-ZnOnanocompositeswith the variation of FA and ZnO have been synthesized by chemical route followed by sintering at 1300?C to produce the end product. To confer the end product, structural (XRD, FTIR) and surface morphological (TEM) studies have been carried out to identify the formation of the nanocomposites. pH level studies has been undertaken to find the feasibility of the prepared composites for different electrochemical bio sensing applications. The optical (UV-VIS) and electrical (IV) characterizations have been carried out to realize the semiconducting nature of the prepared sample. The obtained band gaps of the prepared materials are varying from 2.51 eV to 3.09 eVdepending on the fly ash content in ZnO.
Keywords: Fly ash; Zinc oxide; XRD; TEM; FTIR; UV-VIS.
Selection of materials formulation for non-asbestos friction materials using multi-criteria decision making (MCDM)
by Dinesh Shinde, Mukesh Bulsara, K.N. Mistry
Abstract: Friction materials (FM) should possess higher & stable coefficient of friction at the same time should have high resistance to wear sustained at higher temperature too. In order to develop a friction material exhibiting many functional requirements, one should think from different viewpoints, which gives motivation for use of multi-criteria decision making (MCDM) in selection of materials formulation for the friction materials. In this work, three material formulations (CSP0, CSP15, & CSP30) for friction materials and specimens were prepared as per industry standards. The FMs were subjected to a standard friction material quality test procedure named as Chase friction test under controlled condition as recommended by SAE J661. The results of the chase test were interpreted for two fade & recovery cycles through different attributes crucial to thermal behavior of the FMs and the test data was used in multi-criteria decision making for the selection of best material formulation using Grey Relation Analysis (GRA). To understand the surface wear behavior of the materials, tested samples were subjected to microstructural analysis using SEM/EDS. It is concluded that the materials formulations are ranked as CSP30
Keywords: Friction materials; Fade & recovery; GRA; SEM; EDS.
Influence of Al, Fe, and Cu on the microstructure, diffused reflectance, THz, and dielectric properties for ZnTiO3 nanocrystalline
by Ahmed Bakr, Ali B. Abou Hammad, Ahmed R. Wasswl, Amany M. El Nahrawy, A.M. Mansour
Abstract: Structural, diffused reflectance, THz, and dielectric features of spinel ZnTiO3 doped with (5 mol.% of Al, Cu, and Fe) prepared using the sol-gel and calcined at 800 oC have been investigated. The Al, Cu, and Fe can replace the titanium ions and form sols solutions in the ZnTiO3 phase, and the spectroscopic and dielectric of the ZnTiO3 peaks changed with the dopant addition. X-ray diffraction patterns elucidate the creation of the ZnTiO3 rhombohedral phase, while the introduction of Al and Fe within the ZnTiO3 structure is composed of two phases identified as cubic phase Zn2TiO4 structure and TiO2 besides the rhombohedral of zinc-titanate. The various dopants induce a surface morphology modification observed by SEM. Diffusive reflection for ZnTiO3 doped Al, Cu, and Fe indicated higher transparent over the wavelength 400 nm which making them a choice as excellent transparent semiconductor oxides for different optoelectronic applications. The electric modulus has the least values nearly reach zero at low frequency denoting that a neglected contribution of electrode polarization to the total polarization. THz and dielectric performance of a material is closely related to its composition and microstructure.
Keywords: ZnTiO3-perovskite; Sol-gel method; Diffused reflectance; Terahertz; Dielectric.
Evaluation of Magnesium Recovery in Al-Mg Alloys produced by Modified Stir Casting Method using Genetic Algorithm Optimization Technique
by RAJESH KUMAR BEHERA, BIRAJENDU PRASAD SAMAL, SARAT CHANDRA PANIGRAHI, KAMALAKANTA MUDULI, AEZEDEN MOHAMED, ANANYA SAMAL
Abstract: Generally Al-Mg alloy are used for its light weight and high strength properties in automobile and aeronautical fields. In the present study an attempt is made to investigate the optimum magnesium recovery during the preparation of Al-Mg alloy. The process involves a modified stir casting method where plungers are used to feed magnesium turnings into the molten aluminium metal for Al-Mg alloy production. Use of artificial intelligence technique has been the recent trends in various fields. In the present study, Genetic algorithm has been used as an optimization technique to calculate Mg recovery in the Al-Mg alloys using experimental data. Different genetic operators like crossover and mutation has been used in the computational algorithm for optimized solution.
Keywords: Genetic Algorithm; Modified Stir Casting Method; Furnace Temperature; Al-Mg Alloys; Magnesium Recovery.
An Experimental and Simulation-based analysis of resin flow front during fabrication of lightweight composite components using VARTM process
by Harshit Dave, Himanshu Patel
Abstract: Vacuum Assisted Resin Transfer Molding process is gaining attention in different sectors for lightweight polymer matrix composites. In VARTM process, a flexible vacuum bag is used as a tooling surface. The flexible tooling eliminates the need for precisely matched metal mold making compared to Resin Transfer Molding (RTM) Process. This article is focused on the determination of the permeability of the manmade reinforcements with a rectilinear method. In the rectilinear method, the permeability was determined using a tracked flow front during the resin infusion process. The composite fabrication was carried out using three reinforcements. Total of five stacking sequences was taken for the permeability study. The permeability was determined for five different stacking sequences viz. C-12, G-12, A-12, (CGA)4, (C2G2A2)2. The hybrid stacking sequence (C2G2A2)2 were found more permeable than other stacking sequences. The Hybrid stacking sequence (CGA)4 and G-12 neat glass stacking sequence were found less permeable as the glass fiber fabric architecture found finer than any other reinforcements. For a similar experimental condition, also a simulation study was performed using ANSYS Fluent. In a transient mode simulation, the permeability results were used as input for the flow front simulation. From the experimental and simulation approach, it was found that as the permeability increases the mold filling time is decreases. It was also found that the mold filling time is directly depended on the viscosity of the resin, vacuum pressure, porosity and fiber architecture. The comparison of the simulation and experimental data of the flow front is reported in the present article
Keywords: VARTM; Darcy’s law; Permeability; Flow front; Mold filing.
Characterization of Aluminium and Alumina Thin Films Coatings using different Deposition Methods for Enhancement of Optical Properties
by Harinandan Kumar, Muralidhar Singh M., Sivaiah Potta
Abstract: The enhancement of optical properties such as transmittance, absorptance, and reflectance is possible by applying selective metal and ceramic coatings to the surfaces. Aluminum oxide coatings have potential advantages in this regard. The coating is used for passivation, wear resistance, anti-reflection purpose, etc. in combination with other materials. The aluminum-based coating characteristics include transmittance, reflectance, absorptance, surface roughness, etc. depending on the type of deposition method, operating principles involved, and working conditions maintained during the deposition process. In this study, Aluminium and Alumina thin films of different thicknesses were deposited on borosilicate glass substrates using thermal evaporation, e-beam, and sputtering process with a substrate temperature from 25oC to 100oC. The properties such as transmittance, reflectance, and absorptance were evaluated for the thin film coating. The surface roughness of the thin film was also analyzed. The Rrms values of aluminum and alumina thin films deposited using thermal evaporation and sputtering process with a coating thickness from 100 nm to 300 nm varied from 2 to 5 nm and 1 nm. An increase in reflectance of aluminum coatings was observed with surface roughness.
Keywords: Thin films; Aluminium Coating; Alumina Coating; Thermal Evaporation Method; E-Beam Method; Sputtering Method.
Implementation of topsis optimization technique in comparative analysis of conventional tig and activated tig welding of stainless steel 304L
by Vaibhav Sutar, Baliram Jadhav
Abstract: The Activated tungsten inert gas (TIG) welding mainly focuses on increasing depth of penetration, reducing width of weld, increase speed of welding and improve weld quality. The objective of this Experimental work is to find optimal set of process parameters that achieve higher tensile strength, hardness and depth of penetration. The process parameters selected for Experimental work were welding current, gas flow rate & root gap. The design of experiment was carried out using central composite design of response surface methodology. Silicon dioxide activated flux powder was used along with Acetone for activated TIG welding process. For experimentation austenitic Stainless Steel grade of 304L was used as parent material also the filler material was having same composition. The ANOVA was carried out determine significance of different process parameters on response factors. Further comparative analysis was presented with help of graphs. The TOPSIS optimization approach was used to optimize the factors.
Keywords: Tungsten Inert Gas welding; Tensile strength; Hardness; Response surface methodology; TOPSIS optimization technique.
Evaluation of the Mechanical and Tribological characteristics of AA6061/TiB2 metal matrix composite and parametric optimization of its casting process by using Taguchi Technique and NSGA-II
by Ganesh Suryawanshi, Sachin K. Patil, Ramchandra G. Desavale
Abstract: The present work proposes an experimental methodology and optimization strategy of the process parameters for fabrication of AA6061/TiB2 composite. This composite comprises metal matrix of AA6061 reinforced with TiB2 ceramic and fabricated by stir casting technique. The aim of this work is to find influence of process parameters viz. weight fraction of TiB2 (8%, 10% and 12%), stirrer speed (400rpm, 550 rpm and 700 rpm) and casting temperature (725
Keywords: AA6061/TiB2 metal matrix composite; stir casting; Mechanical properties; Analysis of variance (ANOVA); Signal to noise ratio (S/N); Non-dominated sorting genetic algorithm (NSGA-II).
Effect of Bonded Stepped and Scarf Repair on Impact Damaged Glass Fiber Reinforced Polymer Composite Properties
by Mithun H A, Krishna M, Shrikanth Bailahongal
Abstract: To investigate the effect of bonded stepped and scarf repair methods on the tensile strength restoration was the objective of the present work. The glass fiber composites were fabricated by hand lay-up technique. Impact damage was carried out for two impact energies of 41 J and 44.3 J on the specimens, which was assessed using dye penetration and CAD image scaling technique. Damage repaired specimens were characterized for the tensile test which was carried out on a cut portion of the plate having repair identical to the parent laminate. Tensile strength restoration for 41 J and 44.3 J impact energies of scarf repaired laminates was 69.26 % and 64.19 %, respectively, whereas for step repaired laminates it was 63.46 % and 59.74 % respectively.
Keywords: Damage Repair; Impact; Tensile Test; Glass Epoxy Composites; Dye Penetration.
Prediction of Formability of MIG and TIG welded joints by Erichsen cupping test and Fuzzy-Logic Technique
by Shailesh Dewangan, S. Deepak Kumar, Sanjay Kumar Jha, ANAND PRAKASH
Abstract: The current investigation was carried out to evaluate the formability characteristics of Tungsten inert gas (TIG) and Metal inert gas (MIG) welded parts by conducting Erichsen tests. It is noted that in both the MIG and TIG welded parts, the fracture occurred irrespective of the sheet metal thickness. However, the formability of TIG welds was comparatively better than the MIG weld parts. Further, Fuzzy-logic method was adopted to predict the Erichsen index value and compared with the experimental values. It was observed that Fuzzy-logic predicted values were nearly accurate to the experimental ones, with a minor error of 1.4%. Fuzzy -logic technique is found to be a useful technique to predict the response and in saving time and costly trials on the shop floor, thus beneficial for industrial applications.
Keywords: Erichsen Cupping Test; Fuzzy Logic; MIG TIG welds; Erichsen Index.
Improving the Surface Characteristics of Metallic Implants using Electric Discharge Machining: A Review
by Arvind Kumar Singh, Anup Malik, Harlal Singh Mali
Abstract: The key precondition for choosing bio-materials is their compatibility with the human body, along with the essential properties that would be suitable for long term success of implants. Metallic materials are suitable as implants due to their excellent mechanical properties like toughness, ductility, strength, elasticity etc. For the production of high-performance metallic implants, selection of metal alloys and surface functionalization is of particular importance and necessity. Inspired by the functional surface of natural biological systems, there have recently emerged many new designs and ideas to construct multi-functional surfaces with great potential for biomedical applications. This review initially discusses the metallic biomaterials, their properties, and their applications. The later part of the review discusses surface modification techniques. It was found that electric discharge machining is one of the non-contact type machining processes, which can be useful for economical surface modification of metal implants.
Keywords: biocompatibility; EDM; metallic implants; surface characterization; surface modification.
Effect of Stitch Orientation on Tensile and Flexural Bending Mechanical Properties and Damage Mechanisms of Glass/Epoxy Composites Laminate
by Hamza Mechakra, Samir Lecheb, Ahmed Chellil, Brahim SAFI
Abstract: This study aims to investigate the effect of stitch row directions on tensile and flexural bending mechanical properties of composite laminates reinforced by glass-fabric. For the fabrication of stitched laminates, a polyester thread used to stitch the dry fabric glass in fourth cases (longitudinal stitch 0
Keywords: Stitching; Glass fabrics; Laminates; Tensile; Flexural bending.